Expandable intraluminal graft

ABSTRACT

A plurality of expandable and deformable intraluminal vascular grafts are expanded within a blood vessel by an angioplasty balloon associated with a catheter to dilate and expand the lumen of a blood vessel. The grafts may be thin-walled tubular members having a plurality of slots disposed substantially parallel to the longitudinal axis of the tubular members, and adjacent grafts are flexibly connected by a single connector member disposed substantially parallel to the longitudinal axis of the tubular members.

FIELD OF THE INVENTION

[0001] The invention relates to an expandable intraluminal graft for usewithin a body passageway or duct and, more particularly, expandableintraluminal vascular grafts which are particularly useful for repairingblood vessels narrowed or occluded by disease; and a method andapparatus for implanting expandable intraluminal grafts.

DESCRIPTION OF THE PRIOR ART

[0002] Intraluminal endovascular grafting has been demonstrated byexperimentation to present a possible alternative to conventionalvascular surgery. Intraluminal endovascular grafting involves thepercutaneous insertion into a blood vessel of a tubular prosthetic graftand its delivery via a catheter to the desired location within thevascular system. Advantages of this method over conventional vascularsurgery include obviating the need for surgically exposing, incising,removing, replacing, or bypassing the defective blood vessel.

[0003] Structures which have previously been used as intraluminalvascular grafts have included coiled stainless steel springs; helicallywound coil springs manufactured from an expandable heat-sensitivematerial; and expanding stainless steel stents formed of stainless steelwire in a zig-zag pattern. In general, the foregoing structures have onemajor disadvantage in common. Insofar as these structures must bedelivered to the desired location within a given body passageway in acollapsed state, in order to pass through the body passageway, there isno effective control over the final, expanded configuration of eachstructure. For example, the expansion of a particular coiled spring-typegraft is predetermined by the spring constant and modulus of elasticityof the particular material utilized to manufacture the coiled springstructure. These same factors predetermine the amount of expansion ofcollapsed stents formed of stainless steel wire in a zig-zag pattern. Inthe case of intraluminal grafts, or prostheses, formed of a heatsensitive material which expands upon heating, the amount of expansionis likewise predetermined by the heat expansion characteristics of theparticular alloy utilized in the manufacture of the intraluminal graft.

[0004] Thus, once the foregoing types of intraluminal grafts areexpanded at the desired location within a body passageway, such aswithin an artery or vein, the expanded size of the graft cannot bechanged. If the diameter of the desired body passageway has beenmiscalculated, an undersized graft might not expand enough to contactthe interior surface of the body passageway, so as to be securedthereto. It may then migrate away from the desired location within thebody passageway. Likewise, an oversized graft might expand to such anextent that the spring force, or expansion force, exerted by the graftupon the body passageway could cause rupturing of the body passageway.Further, the constant outwardly radiating force exerted upon theinterior surface of the body passageway can cause erosion of theinternal surface, or intima, of the artery or body passageway.

[0005] Another alternative to conventional vascular surgery has beenpercutaneous balloon dilation of elastic vascular stenoses, orblockages, through use of a catheter mounted angioplasty balloon. Inthis procedure, the angioplasty balloon is inflated within the stenosedvessel, or body passageway, in order to shear and disrupt the wallcomponents of the vessel to obtain an enlarged lumen. With respect toarterial atheroscleerotic lesions, the relatively incompressible plaqueremains unaltered, while the more elastic medial and adventitial layersof the body passageway stretch around the plaque. This process producesdissection, or a splitting and tearing, of the body passageway walllayers, wherein the intima, or internal surface of the artery or bodypassageway, suffers fissuring. This dissection forms a “flap” ofunderlying tissue which may reduce the blood flow through the lumen, orblock the lumen. Typically, the distending intraluminal pressure withinthe body passageway can hold the disrupted layer or flap, in place. Ifthe intimal flap created by the balloon dilation procedure is notmaintained in place against the expanded intima, the intimal flap canfold down into the lumen and close off the lumen, or may even becomedetached and enter the body passageway. When the intimal flap closes offthe body passageway, immediate surgery is necessary to correct thisproblem.

[0006] Although the balloon dilation procedure is typically conducted inthe catheterization lab of a hospital, because of the foregoing problem,it is always necessary to have a surgeon on call should the intimal flapblock the blood vessel or body passageway. Further, because of thepossibility of the intimal flap tearing away from the blood vessel andblocking the lumen, balloon dilations cannot be performed upon certaincritical body passageways, such as the left main coronary artery, whichleads into the heart. If an intimal flap formed by a balloon dilationprocedure abruptly comes down and closes off a critical body passageway,such as the left main coronary artery, the patient could die before anysurgical procedures could be performed.

[0007] Additional disadvantages associated with balloon dilation ofelastic vascular stenoses is that many fail because of elastic recoil ofthe stenotic lesion. This usually occurs due to a high fibrocollagenouscontent in the lesion and is sometimes due to certain mechanicalcharacteristics of the area to be dilated. Thus, although the bodypassageway may initially be successfully expanded by a balloon dilationprocedure, subsequent, early restenosis can occur due to the recoil ofthe body passageway wall which decreases the size of the previouslyexpanded lumen of the body passageway. For example, stenoses of therenal artery at the ostium are known to be refractory to balloondilation because the dilating forces are applied to the aortic wallrather than to the renal artery itself. Vascular stenoses caused byneointimal fibrosis, such as those seen in dialysis-access fistulas,have proved to be difficult to dilate, requiring high dilating pressuresand larger balloon diameters. Similar difficulties have been observed inangioplasties of graft-artery anastomotic strictures andpostendarterectomy recurrent stenoses. Percutaneous angioplasty ofTakayasu arteritis and neurofibromatosis arterial stenoses may show poorinitial response and recurrence which is believed due to the fibroticnature of these lesions.

[0008] For repairing blood vessels narrowed or occluded by disease, orrepairing other body passageways, the length of the body passagewaywhich requires repair, as by the insertion of a tubular prostheticgraft, may present problems if the length of the required graft cannotnegotiate the curves or bends of the body passageway through which thegraft is passed by the catheter. In other words, in many instances, itis necessary to support a length of tissue within a body passageway by agraft, wherein the length of the required graft exceeds the length of agraft which can be readily delivered via a catheter to the desiredlocation within the vascular system. Some grafts do not have therequisite ability to bend so as to negotiate the curves and bendspresent within the vascular system, particularly prostheses or graftswhich are relatively rigid and resist bending with respect to theirlongitudinal axes.

[0009] Accordingly, prior to the development of the present invention,there has been no expandable intraluminal vascular graft for expandingthe lumen of a body passageway, which: prevents recurrence of stenosesin the body passageway; can be utilized for critical body passageways,such as the left main coronary artery of a patient's heart; preventsrecoil of the body passageway wall; allows the intraluminal graft to beexpanded to a variable size to prevent migration of the graft away fromthe desired location and prevents rupturing and/or erosion of the bodypassageway by the expanded graft; permits tissue of an elongated sectionof a body passageway to be supported by an elongated graft; and providesthe necessary flexibility to negotiate the bends and curves in thevascular system. Therefore, the art has sought an expandableintraluminal vascular graft which: prevents recurrence of stenoses inthe body passageway; is believed to be able to be utilized in criticalbody passageways, such as the left main coronary artery of the heart;prevents recoil of the body passageway; can be expanded to a variablesize within the body passageway to prevent migration of the graft awayfrom the desired location and to prevent rupturing and/or erosion of thebody passageway by the expanded graft; permits tissue of an elongatedsection of a body passageway to be supported by an elongated graft; andprovides the necessary flexibility to negotiate the bends and curves inthe vascular system.

SUMMARY OF THE INVENTION

[0010] In accordance with the invention, the foregoing advantages havebeen achieved by the present expandable intraluminal vascular graft. Thepresent invention includes a plurality of thin-walled tubular members,each having first and second ends and a wall surface disposed betweenthe first and second ends, the wall surface having a substantiallyuniform thickness and a plurality of slots formed therein, the slotsbeing disposed substantially parallel to the longitudinal axis of eachtubular member; a single connector member being disposed betweenadjacent tubular members to flexibly connect adjacent tubular members,the single connector member being disposed in a substantially parallelrelationship with respect to the longitudinal axis of the tubularmembers and coplanar with each tubular member; each tubular memberhaving a first diameter which permits intraluminal delivery of thetubular members into a body passageway having a lumen; and the tubularmembers having a second, expanded and deformed diameter, upon theapplication from the interior of the tubular members of a radially,outwardly extending force, which second diameter is variable anddependent upon the amount of force applied to the tubular members,whereby the tubular members may be expanded and deformed to expand thelumen of the body passageway.

[0011] A further feature of the present invention is that the singleconnector member may be a thin-walled, elongate bar member, coplanarwith adjacent tubular members. An additional feature of the presentinvention is that a first connector member may be disposed between thesecond end of a first tubular member and the first end of a secondtubular member; a second connector member may be disposed between thesecond end of the second tubular member and the first end of a thirdtubular member; the first and second connector members being angularlyoffset from one another with respect to the longitudinal axis of thetubular members.

[0012] The expandable intraluminal vascular graft of the presentinvention, when compared with previously proposed prior art intraluminalgrafts, has the advantages of: preventing recurrence of stenoses; isbelieved to permit implantation of grafts in critical at bodypassageways, such as in the left main coronary artery of the heart;prevents recoil of the body passageway; prevents erosion of the bodypassageway by the expanded graft; permits expansion of the graft to avariable size dependent upon conditions within the body passageway;permits tissue of an elongated section of a body passageway to besupported by an elongated graft; and provides the necessary flexibilityto negotiate the bends and curves in tortuous body passageways, such asthe vascular system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In the drawings:

[0014]FIG. 1A is a perspective view of an expandable intraluminalvascular graft, or prosthesis for a body passageway, having a firstdiameter which permits delivery of the graft, or prosthesis, into a bodypassageway;

[0015]FIG. 1B is a perspective view of the graft, or prosthesis, of FIG.1A, in its expanded configuration when disposed within a bodypassageway;

[0016]FIG. 2 is a cross-sectional view of the prosthesis taken alongline 2-2 of FIG. 1B;

[0017]FIG. 3 is a cross-sectional view of an apparatus forintraluminally reinforcing a body passageway, or for expanding the lumenof a body passageway, illustrating a prosthesis, or intraluminalvascular graft, in the configuration shown in FIG. 1A;

[0018]FIG. 4 is a cross-sectional view of the apparatus forintraluminally reinforcing a body passageway, or for expanding the lumenof a body passageway, with the graft, or prosthesis, in theconfigurations shown in FIG. 1B;

[0019]FIGS. 5 and 6 are perspective views of prostheses for a bodypassageway, with the grafts, or prostheses, having a coating thereon;

[0020]FIG. 7 is a perspective view of another embodiment of a graft orprosthesis in accordance with the present invention; and

[0021]FIG. 8 is a perspective view of the graft of FIG. 7, wherein thegraft has been bent or articulated.

[0022] While the invention will be described in connection with thepreferred embodiment, it will be understood that it is not intended tolimit the invention to that embodiment. On the contrary, it is intendedto cover all alternatives, modifications, and equivalents, as may beincluded within the spirit and scope of the invention as defined by theappended claims.

DETAILED DESCRIPTION OF THE INVENTION

[0023] In FIGS. 1A and 1B, an expandable intraluminal vascular graft, orexpandable prosthesis for a body passageway, 70 is illustrated. Itshould be understood that the terms “expandable intraluminal vasculargraft” and “expandable prosthesis” are interchangeably used to someextent in describing the present invention, insofar as the methods,apparatus, and structures of the present invention may be utilized notonly in connection with an expandable intraluminal vascular graft forexpanding partially occluded segments of a blood vessel, or bodypassageway, but may also be utilized for many other purposes as anexpandable prosthesis for many other types of body passageways. Forexample, expandable prostheses 70 may also be used for such purposes as:(1) supportive graft placement within blocked arteries opened bytransluminal recanalization, but which are likely to collapse in theabsence of an internal support; (2) similar use following catheterpassage through mediastinal and other veins occluded by inoperablecancers; (3) reinforcement of catheter created intrahepaticcommunications between portal and hepatic veins in patients sufferingfrom portal hypertension; (4) supportive graft placement of narrowing ofthe esophagus, the intestine, the ureters, the urethra; and (5)supportive graft reinforcement of reopened and previously obstructedbile ducts. Accordingly, use of the term “prosthesis” encompasses theforegoing usages within various types of body passageways, and the useof the term “intraluminal vascular graft” encompasses use for expandingthe lumen of a body passageway. Further, in this regard, the term “bodypassageway” encompasses any duct within the human body, such as thosepreviously described, as well as any vein, artery, or blood vesselwithin the human vascular system.

[0024] Still with reference to FIGS. 1A and 1B, the expandableintraluminal vascular graft, or prosthesis, 70 is shown to generallycomprise a tubular member 71 having first and second ends 72, 73 and awall surface 74 disposed between the first and second ends 72, 73.Tubular member 71 has a first diameter, d, which, to be hereinafterdescribed in greater detail, permits intraluminal delivery of thetubular member 71 into a body passageway 80 having a lumen 81 (FIG. 3).With reference to FIG. 1B, upon the application from the interior of thetubular member 71 of a radially, outwardly extending force, to behereinafter described in greater detail tubular member 71 has a second,expanded diameter, d′, which second diameter d′ is variable in size anddependent upon the amount of force applied to deform the tubular member71.

[0025] Tubular member 71, may be any suitable material which iscompatible with the human body and the bodily fluids (not shown) withwhich the vascular graft, or prosthesis, 70 may come into contact.Tubular member 71 must also be made of a material which has therequisite strength and elasticity characteristics to permit the tubularmember 71 to be expanded and deformed from the configuration shown inFIG. 1A to the configuration shown illustrated in FIG. 1B and further topermit the tubular member 71 to retain its expanded and deformedconfiguration with the enlarged diameter d′ shown in FIG. 1B and resistradial collapse. Suitable materials for the fabrication of tubularmember 71 would include silver, tantalum, stainless steel, gold,titanium or any suitable plastic material having the requisitecharacteristics previously described.

[0026] Preferably, tubular member 71 is initially a thin-walledstainless steel tube having a uniform wall thickness;, and a pluralityof slots 82 are formed in the wall surface 74 of tubular member 71. Asseen in FIG. 1A when tubular member 71 has the first diameter d, theslots 82 are disposed substantially parallel to the longitudinal axis ofthe tubular member 71. As seen in FIG. 1A, the slots 82 are preferablyuniformly and circumferentially spaced from adjacent slots 82, as byconnecting members 77, which connecting members 77 preferably have alength equal to the width of slots 82, as seen in FIG. 1A. Slots 82 arefurther uniformly spaced from adjacent slots 82 along the longitudinalaxis of the tubular member 71, which spacing is preferably equal to thewidth of connecting members 77. Thus, the formation of slots 82 resultsin at least one elongate member 75 being formed between adjacent slots82, elongate member 75 extending between the first and second ends, 72,73 of tubular member 71, as seen in FIG. 1A.

[0027] Still with reference to FIG. 1A, each slot will have first andsecond ends with a connecting member 77 disposed at the first and secondends of slots 82. Preferably, the first and second ends of each slot 82are disposed intermediate the first and second ends of adjacent slots 82along the longitudinal axis of the tubular member 71. Thus, connectingmembers 77, which are disposed at the first and second ends of each slot82, and between elongate members 75, will in turn be disposedintermediate the first and second ends of adjacent slots 82 along thelongitudinal axis of the tubular member 71. Accordingly, slots 82 arepreferably uniformly and circumferentially spaced from adjacent slots,and slots 82 adjacent to one another along the longitudinal axis oftubular member 71 are in a staggered relationship with one another.Alternating slots disposed about the circumference of tubular member 71at both the first and second ends 72, 73 of tubular member 71 will onlyhave a length equal to approximately one-half of the length of acomplete slot 82, such half-slot 82 being bounded by members 78, 79, atboth the first and second ends 72, 73 of tubular member 71. Although thegraft, or prosthesis, 70 of FIGS. 1A and 1B is illustrated to have alength approximately equal to the length of two slots 82, it should beapparent that the length of the graft 70 could be made longer or shorteras desired.

[0028] The foregoing described construction of graft, or prosthesis, 70permits graft, or prosthesis, 70 to be expanded uniformly, andoutwardly, in a controlled manner into the configuration shown in FIG.1B, upon the application of a suitable force from the interior oftubular member 71, as will be hereinafter described in greater detail.The expansion of tubular member 71 into the configuration shown in FIG.1B is further uniform along the length of tubular member 71, not onlybecause of the uniform spacing between slots 82, as previouslydescribed, but also because the thickness of the wall surface 74, or thethickness of connecting members 77, elongate members 75, and members 78,79, is the same uniform thickness. As illustrated in FIG. 2, the uniformthickness of elongate member 75 is shown, and the preferredcross-sectional configuration of elongate member 75, connecting member77, and members 78, 79, is illustrated, which configuration isrectangular. It should of course be understood by those skilled in theart, that the cross-sectional configuration of the foregoing componentsof graft, or prosthesis, 70 could also be square, rectangular, or othercross-sectional configurations. As will be hereinafter described ingreater detail, it is preferable that the outer surface 74 of graft, orprothesis, 70, which would be in contact with the body passageway 80FIG. 4, should be relatively smooth.

[0029] With reference to FIG. 1B, it is seen that after the graft, orprosthesis 70, has been expanded and deformed into the configuration ofFIG. 1B, the slots 82 will assume a substantially hexagonalconfiguration when the tubular member 71 has the second, expandeddiameter, d′, as shown in FIG. 1B. Such a hexagonal configuration willresult when the slots 82 initially have a substantially rectangularconfiguration when the tubular member 71 has the first diameter, d,illustrated in FIG. 1A. It should be noted that were the width of slots82 to be substantially reduced, whereby the length of connecting member77 would approximate a single point intersection, the expansion of sucha tubular member 71 would result in slots 82 assuming a configurationwhich would be substantially a parallelogram (not shown).

[0030] It should be noted that not only is tubular member 71 expandedfrom the configuration shown in FIG. 1A to achieve the configurationshown in FIG. 1B, but tubular member 71 is further “deformed” to achievethat configuration. By use of the term “deformed” is meant that thematerial from which graft, or prosthesis, 70 is manufactured issubjected to a force which is greater than the elastic limit of thematerial utilized to make tubular member 71. Accordingly, the force issufficient to permanently bend elongate members 75 whereby segments ofthe elongate members 75 pivot about connecting members 77 and move in acircumferential direction as they pivot, whereby the diameter of thetubular member 71 increases from the first diameter, d, to the expandeddiameter, d′, of FIG. 1B. The force to be applied to expand tubularmember 71, which is applied in the manner which will be hereinafterdescribed in greater detail, must thus be sufficient to not only expandtubular member 71, but also to deform elongate member 75, in the mannerpreviously described, whereby the portions of the elongate members 75which pivot about the ends of connecting members 77 do not “spring back”and assume their configuration shown in FIG. 1A, but rather retain theconfiguration thereof in FIG. 1B. Once graft, or prosthesis, 70 has beenexpanded and deformed into the configuration shown in FIG. 1B, graft, orprosthesis 70, will serve to prevent a body passageway from collapsingas will be hereinafter described in greater detail. It should be notedthat when tubular member 71 has the first diameter, d, shown in FIG. 1A,or after tubular member 71 has been expanded and deformed into thesecond, expanded diameter, d′, of FIG. 1B, tubular member 71 does notexert any outward, radial force, in that tubular member 71 is not a“spring-like” or “self-expanding member”, which would tend to exert anoutwardly radial force.

[0031] With reference now to FIGS. 3 and 4, apparatus of the presentinvention will be described in greater detail. Once again, it should beunderstood that the apparatus of the present invention is useful notonly for expanding the lumen of a body passageway, such as an artery,vein, or blood vessel of the human vascular system, but are also usefulto perform the previously described procedures to intraluminallyreinforce other body passageways or ducts, as previously described.Still with reference to FIGS. 3 and 4, an expandable intraluminalvascular graft, or prosthesis, 70, of the type described in connectionwith FIGS. 1A and 1B, is disposed or mounted upon a catheter 83.Catheter 83 has an expandable, inflatable portion 84 associatedtherewith. Catheter 83 may include means for mounting and retaining 85the expandable intraluminal vascular graft, of prosthesis, 70 on theexpandable, inflatable portion 84 of catheter 83. The mounting andretaining means 85 could comprise retainer ring members 86 disposed onthe catheter 83 adjacent the expandable inflatable portion 84 ofcatheter 83; and a retainer ring member 86 is disposed adjacent each end72, 73 of the expandable intraluminal vascular graft, or prosthesis, 70.As seen in FIG. 3, retainer ring members could be formed integral withcatheter 83, and the retainer ring member 86 adjacent the leading tip 87of catheter 83 slopes upwardly and away from catheter tip 87 in order toprotect and retain graft or prosthesis, 70 as it is inserted into thelumen 81 of body passageway 80, as to be hereinafter described ingreater detail. The remaining retainer ring member 86 as shown in FIG.3, slopes downwardly away from tip 87 of catheter 83, to insure easyremoval of catheter 83 from body passageway 80. After expandableintraluminal graft, or prosthesis, 70 has been disposed upon catheter83, in the manner previously described, the graft, or prosthesis, 70 andcatheter 83 are inserted within a body passageway 80 by catheterizationof the body passageway 80 in a conventional manner.

[0032] In a conventional manner, the catheter 83 and graft, orprosthesis, 70 are delivered to the desired location within the bodypassageway 80, whereat it is desired to expand the lumen 81 of bodypassageway 80 via intraluminal graft 70, or where it is desired toimplant prosthesis 70. Fluoroscopy, and/or other conventional techniquesmay be utilized to insure that the catheter 83 and graft, or prosthesis,70 are delivered to the desired location within the body passageway.Prosthesis, or graft, 70 is then a controllably expanded and deformed bycontrollably expanding the expandable, inflatable portion 84 of catheter83, whereby the prosthesis, or graft, 70 is expanded and deformedradially, outwardly into contact with the body passageway 80, as shownin FIG. 4. In this regard, the expandable, inflatable portion ofcatheter 83 may be a conventional angioplasty balloon 88. After thedesired expansion and deformation of prosthesis, or graft, 70 has beenaccomplished, angioplasty balloon 88 may be collapsed, or deflated, andthe catheter 83 may be removed in a conventional manner from bodypassageway 80. If desired, as seen in FIG. 3, catheter 83, having graftor prosthesis, 70 disposed thereon, may be initially encased in aconventional Teflon sheath 89, or a sheath 89 made of another suitablematerial, which is pulled away from prosthesis, or graft, 70, prior toexpansion of the prosthesis, or graft, 70.

[0033] Still with reference to FIGS. 3 and 4, it should be noted thattubular member 71 of prosthesis, or graft, 70 initially has the firstpredetermined, collapsed diameter, d, as described in connection withFIG. 1A, in order to permit the insertion of the tubular member, 71 intothe body passageway 80 as previously described. When it is desired toimplant prosthesis 70 within a body passageway 80 for the purposespreviously described, the prosthesis 70 is, controllably expanded anddeformed to the second diameter, d′, and the second, expanded diameter,d′, is variable and determined by the internal diameter of the bodypassageway 80, as shown in FIG. 4, and by the amount of expansion of theinflatable portion 84 of catheter 83. Accordingly, the expanded anddeformed prosthesis 70, upon deflation of angioplasty balloon 88 willnot be able to migrate from the desired location within the bodypassageway 80, nor will the expansion of the prosthesis 70 be likely tocause a rupture of the body passageway 80. Furthermore, insofar asprosthesis, or graft, 70 is not a “spring-like” or “self-expandingmember”, the prosthesis is not consistently applying an outward, radialforce against the interior surface of body passageway 80, in excess ofthat required to resist radial collapse of the body passageway 80. Thus,erosion of the interior surface, or intima, of the artery or bodypassageway is prevented.

[0034] When it is desired to use expandable intraluminal graft 70 toexpand the lumen 81 of a body passageway 80 having an area of stenosis,the expansion of intraluminal vascular graft 70 by angioplasty balloon88, allows controlled dilation of the stenotic area and, at the sametime controlled expansion and deformation of the vascular graft 70,whereby vascular graft 70 prevents the body passageway 80 fromcollapsing and decreasing the size of the previously expanded lumen 81.Once again, the second, expanded diameter d′ of intraluminal vasculargraft 70, as shown in FIG. 4, is variable and determined by the desiredexpanded internal diameter of body passageway 80. Thus, the expandableintraluminal graft 70 will not migrate away from the desired locationwithin the body passageway 80 upon deflation of angioplasty balloon 88,nor will the expansion of intraluminal graft 70 likely cause a ruptureof body passageway 80, nor any erosion as previously described. Further,should an intimal flap, or fissure, be formed in body passageway 80 atthe location of graft 70, graft 70 will insure: that such an intimalflap will not be able to fold inwardly into body passageway 80, nor tearloose and flow through body passageway 80. In the situation of utilizinggraft 70 in the manner previously described to expand the lumen of aportion of a critical body passageway, such as the left main coronaryartery, it is believed that the intimal flap will be unable to occludethe left main coronary artery of the heart and cause the death of thepatient.

[0035] Because it is only necessary to inflate angioplasty balloon 88one time in order to expand and deform graft 70, it is believed that agreater amount of endothelium, or inner layer of the intima, or innersurface of the body passageway, will be preserved, insofar as the extentof endothelial denudation during transluminal angioplasty isproportional to the balloon inflation time. Further, in theory, theamount of preserved endothelium should be large because in the expandedconfiguration of graft 70, potentially 80% of the endothelium is exposedthrough the openings or expanded slots 82 of graft 70. It is furtherbelieved that intact patches of endothelium within expanded slots 82 ofgraft 70 may result in a rapid, multicentric endothelialization patternas shown by experimental studies.

[0036] With reference now to FIGS. 5 and 6, prostheses, or grafts, 70 ofthe type previously described in connection with FIGS. 1A and 1B areshown, and the tubular members 71 of grafts, or prostheses, 70 have abiologically inert or biologically compatible coating 90 placed uponwall surfaces 74 of tubular shaped members 71. Examples of a suitablebiologically inert coating would be porous polyurethane, Teflon , orother conventional biologically inert plastic materials. The coating 90should be thin and highly elastic so as not to interfere with thedesired expansion and deformation of prosthesis, or graft, 70. Coating90 may be further provided with a means for anchoring 91 (FIG. 6) thetubular member 71 to the body passageway 80. Anchoring means 91 may becomprised of a plurality of radially, outwardly extending projections 92formed on the coating 90. As seen in FIG. 6, the radially outwardlyextending projections 92 could comprise a plurality of ridges 93, orother types of radially, outwardly extending projections. Further, itmay be desirable to have a plurality of openings 94 formed in coating90, as shown in FIG. 5, whereby the fluid contained in body passageway80 can be in direct contact with the dilated, or expanded, bodypassageway area. Examples of biologically compatible coatings 90 wouldinclude coatings made of absorbable polymers such as those used tomanufacture absorbable sutures. Such absorbable polymers includepolyglycoides, polylactides, and copolymers thereof. Such absorbablepolymers could also contain various types of drugs, whereby as thecoating 90 is absorbed, or dissolves, the drug would be slowly releasedinto the body passageway 80.

[0037] Turning now to FIGS. 7 and 8, an expandable intraluminal vasculargraft, or prosthesis, 70′ is shown for implantation in curved bodypassageways 80, or for use in the elongated sections of body passageway80, when a prosthesis or a graft, 70′ is required which is longer thanthe graft, or prosthesis, 70 of FIG. 1A. Identical reference numeralsare used throughout FIGS. 7 and 8 for elements which are the same indesign, construction, and operation, as those previously described inconnection with FIGS. 1A-6, and primed reference numerals are used forelements which are similar in construction, design, and operation, asthose previously described in connection with 1A-6.

[0038] As seen in FIG. 7, graft, or prosthesis, 70′ generally includes aplurality of prostheses, or grafts, 70 as described previously inconnection with FIGS. 1A, 1B, and 2. Disposed between adjacent tubularmembers, 71, or adjacent grafts, or prostheses, 70, is a singleconnector member 100 to flexibly connect adjacent tubular members 71 orgrafts, or prostheses, 70. Connector members 100 are preferably formedof the same material as grafts 70, as previously described, andconnector members 100 may be formed integrally between adjacent grafts70, or tubular members 71, as shown in FIG. 7. The cross-sectionalconfiguration of connector members 100, along the longitudinal axis ofgraft, or prosthesis, 70′, is the same, in that connector members 100have the same uniform wall thickness of elongate members 75 and thusform a thin-walled, elongate bar member 101 which is coplanar withadjacent tubular members 71. Of course, it should be readily apparent toone of ordinary skill in the art, that the thickness of connectormembers 100 could alternatively be smaller than elongate member 75;however, it is preferable that the outer circumferential surface 102 ofconnector members 100 lies in the same plane formed by the wall surfaces74 of grafts, or prostheses, 70, as seen in FIG. 7.

[0039] Still with reference to FIGS. 7-8, it should be noted thatalthough graft, or prosthesis, 70 is illustrated as including threegrafts, or prostheses, 70 flexibly connected to one another by connectormembers 100, as few as two grafts 70 could be connected to form graft,or prosthesis, 70′. Furthermore, many grafts 70 could be flexiblyconnected by connector members 100 as are desired to form graft, orprosthesis, 70′. Preferably, the length of each graft, or prosthesis, 70is approximately the length of two slots 82; however, the length of eachgraft 70 could be approximately equal to the length of two or more slots82. When three or more grafts 70 are flexibly connected by connectormembers 100, as shown in FIGS. 7 and 8, preferably a first connectormember 100 is disposed between the second end 73 of a first tubularmember 70A and the first end 72 of a second tubular member 70B. A secondconnector member 100 is then disposed between the second end 73 of thesecond tubular member 70B and the first end 72 of a third tubular member70C. The first and second connector members 100, as shown in FIGS. 7 and8, may be angularly offset from one another with respect to thelongitudinal axis of the tubular members 70 to permit the requisiteflexibility between the interconnected grafts, or prostheses, 70.

[0040] The delivery and expansion of graft, or prosthesis, 70′ is thesame as that previously described in connection with FIGS. 1A, 1B, and3-4. The length of the expandable, inflatable portion 84 of catheter 83would be sized to conform with the length of the graft, or prosthesis,70′, as should be readily apparent to one of ordinary skill in the art.Except for the length of the expandable, inflatable portion 84, catheter83, the method of delivery of graft, or prosthesis, 70′ and itssubsequent, controllable expansion and deformation are the same aspreviously described. As seen in FIG. 8, the prosthesis 70′ isillustrated in the configuration it would assume when being delivered tothe desired location within the body passageway 80, and the graft, orprosthesis, 70′ is disposed upon catheter 83 and is passing through acurved portion of body passageway 80, such as an arterial bend. Becauseof the disposition of flexible connector members 100 between adjacenttubular members 71, or grafts, or prostheses, 70, graft, or prosthesis,70′ is able to flexibly bend, or articulate, with respect to thelongitudinal axis of graft, or prosthesis, 70′, so as to be able tonegotiate the curves or bends found in body passageways 80. It should benoted that connector members 100 permit the bending, or articulation ofadjacent tubular members 71 in any direction about the longitudinal axisof graft, or prosthesis, 70′. When graft, or prosthesis, 70′ is in itsexpanded, and deformed configuration, tubular members 71 of graft, orprosthesis, 70′, will assume the configuration shown in FIG.

[0041] It is to be understood that the invention is not to be limited tothe exact details of construction, operation, exact materials, orembodiments shown and described, as obvious modifications andequivalents will be apparent to one skilled in the art. Accordingly, theinvention is therefore to be limited only by the scope of the appendedclaims. APPENDIX A ASSIGNED PATENTS EXPANDABLE INTRALUMINAL GRAFT, ANDMETHOD AND APPARATUS FOR IMPLANTING AN EXPANDABLE INTRALUMINAL GRAFT.INVENTOR: JULIO C PALMAZ SPC0307 USA ISSUED 06/796009 4733665 11/07/2005SPC0307 USA1 REX ISSUED 90/002493 B14733665 11/07/2005 SPC0307 USA4 REXPENDING 90/004916 SPC0307 USA3 REX PENDING 90/004786 EXPANDABLEINTRALUMINAL GRAFT, AND METHOD AND APPARATUS FOR IMPLANTING ANEXPANDABLE INTRALUMINAL GRAFT. INVENTOR: JULIO C PALMAZ SPC0307 USA2 CIPISSUED 06/878821 4776337 10/11/2005 SPC0308 EXPANDABLE INTRALUMINALGRAFT, AND METHOD AND APPARATUS FOR IMPLANTING AN EXPANDABLEINTRALUMINAL GRAFT. INVENTOR: JULIO C PALMAZ SPC0308 USA CIP ISSUED06/923798 4739762 04/26/2006 SPC0308 USA1REX ISSUED 90/004916 B1473976204/26/2006 SPC0412 EXPANDABLE INTRALUMINAL GRAFT, AND METHOD ANDAPPARATUS FOR IMPLANTING AN EXPANDABLE INTRALUMINAL GRAFT INVENTOR:JULIO C PALMAZ RICHARD A SCHATZ SPC0412 USA CIP ISSUED 07/174246 510241704/07/2009 SPC0413 EXPANDABLE INTRALUMINAL GRAFT INVENTOR: RICHARD ASCHATZ SPC0413 USA ABANDONED 07/253115 10/04/1988 SPC0470 EXPANDABLEINTRALUMINAL GRAFT INVENTOR: RICHARD A SCHATZ SPC0470 USA CON ISSUED07/657296 5195984 03/23/2010 SPC0522 EXPANDABLE INTRALUMINAL GRAFTINVENTOR: RICHARD A SCHATZ SPC0522 USA CON. PENDING 07/980667 11/24/1992SPC0516 METHOD AND APPARATUS FOR BILATERAL INTRA-AORTIC BYPASSINVENTORS: JULIO C PALMAZ JEAN CLAUDE LABORDE SPC0516 USA ISSUED07/818052 5316023 01/08/2012 SPC0564 METHOD AND APPARATUS FOR BILATERALINTRA-AORTIC BYPASS INVENTORS: JULIO C PALMAZ JEAN CLAUDE LABORDESPC0564 USA DIV. ABANDONED 08/199118 02/22/1994 DIV. OF SPC 516. SPC0565METHOD AND APPARATUS FOR BILATERAL INTRA-AORTIC BYPASS INVENTORS: JULIOC PALMAZ JEAN CLAUDE LABORDE SPC0565 USA DIV. ISSUED 08/199119 557117011/05/2013 SEE REISSUE APPLICATION SPC0794 SPC0648 APPARATUS FORBILATERAL INTRA-AORTIC BYPASS INVENTOR: JULIO C PALMAZ SPC0648 USA DIV.ISSUED 08/588454 5683453 01/08/2012 SPC0794 METHOD AND APPARATUS FORBILATERAL INTRA-AORTIC BYPASS INVENTORS: JULIO C PALMAZ JEAN C LABORDESPC0794 USA REISSUE PENDING 09/ - - - 11/05/1998

1. An expandable intraluminal vascular graft, comprising: a plurality of thin-walled tubular members, each having first and second ends and a wall surface disposed between the first and second ends, the wall surface having a substantially uniform thickness and a plurality of slots formed therein, the slots being disposed substantially parallel to the longitudinal axis of each tubular member; a single connector member being disposed between adjacent tubular members to flexibly connect adjacent tubular members, the single connector member being disposed in a substantially parallel relationship with respect to the longitudinal axis of the tubular members and coplanar with each tubular member. each tubular member having a first diameter which permits intraluminal delivery of the tubular members into a body passageway having a lumen; and the tubular members having a second, expanded and deformed diameter, upon the application from the interior of the tubular members of a radially, outwardly extending force, which second diameter is variable and dependent upon the amount of force applied to the tubular members, whereby the tubular members may be expanded and deformed to expand the lumen of the body passageway.
 2. The expandable intraluminal graft of claim 1, wherein the single connector member is a thin-walled, elongate bar member, coplanar with adjacent tubular members.
 3. The expandable intraluminal graft of claim 1, wherein a first connector member is disposed between the second end of a first tubular member and the first end of a second tubular member; a second connector member is disposed between the second end of the second tubular member and the first end of a third tubular member, the first and second connector members being angularly offset from one another with respect to the longitudinal axis of the tubular members.
 4. An expandable prosthesis for a body passageway, comprising: a plurality of thin-walled tubular members, each having first and second ends and a wall surface disposed between the first and second ends, the wall surface having a substantially uniform thickness and a plurality of slots formed therein, the slots being disposed substantially parallel to the longitudinal axis of each tubular member; a single connector member being disposed between adjacent tubular members to flexibly connect adjacent tubular members, the single connector member being disposed in a substantially parallel relationship with respect to the longitudinal axis of the tubular members and coplanar with each tubular member; each tubular member having a first diameter which permits intraluminal delivery of the tubular members into a body passageway having a lumen; and the tubular members having a second, expanded and deformed diameter, upon the application from the interior of the tubular members, of a radially, outwardly extending force, which second diameter is variable and dependent upon the amount of force applied to the tubular member, whereby the tubular member may be expanded and deformed to expand the lumen of the body passageway.
 5. The expandable prosthesis of claim 4, wherein the single connector member is a thin-walled, elongate bar member, coplanar with adjacent tubular members.
 6. The expandable prosthesis of claim 4, wherein a first connector member is disposed between the second end of a first tubular member and the first end of a second tubular member; a second connector member is disposed between the second end of the second tubular member and the first end of a third tubular member, the first and second connector members being angularly offset from one another with respect to the longitudinal axis of the tubular members. 